Planning that acknowledges spatial differences in the services mangroves provide

KEY MESSAGES:

The value of ecosystem services can vary greatly across relatively small scales

Equity in rural areas is a key concern, particularly in data- poor regions

For much of our recent history societies have often viewed mangroves as swamps, health hazards, and only good for draining and developing. Yet, fast forward to the present day and it’s widely acknowledged that mangroves are anything but wastelands, and do in fact generate highly valuable services such as coastal protection, habitat for wildlife, breeding grounds for fisheries, and carbon storage. This is especially the case in developing Pacific nations where mangroves provide vital services that contribute enormously to both the economy and the wellbeing of local peoples and cultures.

Mangroves provide a range of valued ecosystem services. New research is enabling managers and policy makers to take this into account in their decision making. (Image by Scott Atkinson)

Despite their value, mangroves are an ecosystem under threat. Up to a third of mangroves around the world have been cleared for coastal development and aquaculture since 1980. And what is left is facing pressure from other factors including climate change and rising sea levels. The resources available to save this precious ecosystem are scarce so it is important to invest them wisely.

Recently, we have developed an approach that helps prioritise investments in mangrove conservation in a way that takes into account the different values of the ecosystem services that individual mangroves provide across a management area. We demonstrated the value of this approach by mapping multiple ecosystem services being provided by Fiji’s mangroves and their relative value across all of Fiji. Our new approach could prove vital to policy makers and funding organisations seeking specific policy outcomes when planning investments in mangrove ecosystems.

Incorporating the values of the services that ecosystems provide into decision making is becoming increasingly common in nature conservation and resource management. However, with limited funds for conservation, identifying priority areas where investment efficiently conserves multiple ecosystem services becomes incredibly important.

We showed this could be done by mapping four mangrove ecosystems services (coastal protection, fisheries, biodiversity, and carbon storage) across Fiji. Using a cost-effectiveness analysis, we ranked mangrove areas for each of those four services, where the effectiveness of managing the mangrove was a function of the benefits provided to the local communities, and the costs were associated with restricting specific uses of the mangrove.

We found that different areas of mangroves around Fiji provided different values of the individual ecosystem services. Spatially explicit mapping such as this can help decision-makers direct funding to localities that best meet specific funding objectives. For example, financing for disaster-risk reduction and climate adaptation (eg, from the Green Climate Fund) can be directed toward mangrove areas with the highest coastal protection services. Biodiversity funds (eg, from the Global Environment Facility) can be directed towards areas with the highest potential to conserve species.

Presently, funding for biodiversity in Fiji has been ‘bundled’ with funding for climate adaptation and sustainable land management. As a consequence, this funding has been directed to some of the most degraded habitats in the country. This might improve sustainable land management but it’s likely a major lost opportunity for effective biodiversity financing and conservation. Examples such as this demonstrate why it’s important to distinguish between areas that provide differing levels of ecosystem services.

We also believe our approach might help in the designation of ‘no-go zones’ for development in Fiji based on their national significance for the provisioning and value of ecosystem services. Our national-scale assessment might allow for guiding the selection of the highest priority areas for each ecosystem service where development and extractive activities are not allowed.

There are many challenges with this type of approach (indeed, with any form of spatial planning). Mapping exercises such as this need to deal with issues of poor data availability and associated equity concerns in rural areas, where available data is often even less reliable. However, we believe our approach provides a significant improvement on existing approaches that either deal with a single ecosystem service, ignore them all together, or do not account for the spatial differences in ecosystem services across entire management areas.